# Calendar vs Readwise Highlights

The clearest difference is price: Readwise Highlights at Free against Calendar's $31.99. Readwise Highlights also leads on update cadence (every 2 weeks vs every 31 months). Calendar's advantage is in-app purchases (none vs 8). On ads, device support and iOS requirement there is nothing between them.

Readwise Highlights is free to download; Calendar costs $31.99 up front. Readwise Highlights sells 8 in-app purchases, starting at $4.99 per month. Calendar asks for nothing beyond the download.

Calendar ships an update every 31 months, Readwise Highlights every 2 weeks. The most recent releases landed on October 18, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Calendar | Readwise Highlights |
| --- | --- | --- |
| Price | $31.99 | **Free** |
| Rating | — | **[4.8 (1.5K ratings)](https://appshunter.io/ios/app/readwise-highlights/id1476885528/reviews)** |
| Number of ratings | — | **1.5K** |
| Positive reviews | — | 69.3% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 31 months | **Every 2 weeks** |
| Monetization | — | Free with in-app purchases |
| Size | 1 MB | 112 MB |
| Requires iOS | 15.6 | **15.5** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 12+ |
| Developer | [Martin Eisele](https://appshunter.io/developer/1099492467) | [Readwise, Inc](https://appshunter.io/developer/1476885527) |

## What reviewers say

### Calendar

[App page](https://appshunter.io/ios/app/calendar-trainer/id1293920342)

**In-app purchases:** none


### Readwise Highlights

[App page](https://appshunter.io/ios/app/readwise-highlights/id1476885528)

This app helps you retain more of what you read by centralizing and revisiting your highlights from various reading platforms. It uses spaced repetition and active recall techniques to improve memory and offers features like tagging, note-taking, and OCR for physical books.

**Highlights:** Synchronize highlights from multiple platforms, Daily review habit via app and email, Spaced repetition and active recall, Tag, note, and search highlights, OCR for paper book highlights, Convert highlights to flashcards

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Readwise Lite Monthly | $4.99 | per month |
| Readwise Lite Monthly | $6.99 | per month |
| Readwise Full Monthly Plan | $8.99 | per month |
| Readwise Full Monthly | $12.99 | per month |
| Readwise Lite Yearly | $52.99 | per year |
| Readwise Lite Yearly | $66.99 | per year |
| Readwise Full Yearly | $94.99 | per year |
| Readwise Full Yearly | $119.99 | per year |

**What reviewers like**

- 🚀 Powerful spaced repetition
- 📚 Seamless integration with reading apps
- 🔍 Helpful AI-powered features
- 🗓️ Useful daily review routine
- 🧠 Boosts knowledge retention

**What reviewers complain about**

- 💰 Expensive subscription
- 🔌 Sync issues with some platforms
- 📱 Subpar mobile app experience
- 🕰️ Lack of flexibility in daily review
- 🔍 Limited search functionality

**Reported bugs**

- Frequent app crashes
- Sync failures with certain accounts
- Unreliable highlight capture

**Requested features**

- Add support for more reading apps
- Improve sync and import capabilities
- Introduce more customization options
- Enhance search and organization tools
- Develop a more intuitive mobile interface


## Frequently asked questions

### Is Calendar free?

Calendar costs $31.99, with no in-app purchases.

### Is Readwise Highlights free?

Readwise Highlights is free to download, with in-app purchases available.

### Do Calendar or Readwise Highlights have ads?

Neither Calendar nor Readwise Highlights shows ads.

### Which is updated more often, Calendar or Readwise Highlights?

Calendar ships an update every 31 months, and Readwise Highlights every 2 weeks. Most recently, Calendar was updated on October 18, 2026 and Readwise Highlights on October 29, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*